Changes in Blood and Semen Quality of Bulls after Artificial Infection with Mycoplasma wenyonii

[目的]验证温氏枝原体对种公牛血液和精液品质的影响。[方法]将10头健康的鲁西黄牛的种公牛随机分成2组,试验组分别于试验当天和第28天静脉注射温氏枝原体,从临床症状、血液涂片镜检、血液生理生化、精液品质和阴囊变化等方面,综合评价温氏枝原体对种公牛的影响。[结果]除个别指标外,试验组临床检查基本正常,未出现明显的血液和精液品质异常。[结论]该研究表明人工感染温氏枝原体对种公牛毒力较低,致病性不强,对血液和精液品质无明显异常。     

Monoparesis in association with feline pulmonary carcinoma: A literature review with 3 new cases

We describe 3 cases of cats that were presented with a sudden onset of monoparesis as a result of arterial thromboembolism without evidence of cardiovascular disease that were subsequently diagnosed with a primary pulmonary carcinoma. Arterial tumor thromboemboli due to pulmonary carcinoma should be considered as a differential diagnosis in cases of lameness or paresis in older cats. We theorize that large tumor emboli may obstruct peripheral arteries leading to acute monoparesis.     

Control of colonial hydroid macrofouling by free-field ultrasonic radiation

Free-field ultrasonic radiation inhibited the feeding of the macrofouling hydroid Garveia franciscana by causing tentacle contraction at the sonic degasification threshold. Within the frequency range of 250 to 2000 kilohertz, the threshold sound intensity (sonic degasification threshold) that caused tentacle contraction was directly proportional to frequency, with the minimum observed being 0.6 watt per square centimeter at 250 kilohertz. A pulse length of 0.2 second and interpulse period of 102 seconds gave the lowest average power required to produce tentacle contraction at a peak pulse sound intensity of 6.2 watts per square centimeter with a frequency of 250 kilohertz. Twenty-four hour exposures to the sound regime caused destruction of the hydranths and regression of tissue in the stolons.     

Climate impact on plankton ecosystems in the Northeast Atlantic

It is now widely accepted that global warming is occurring, yet its effects on the world's largest ecosystem, the marine pelagic realm, are largely unknown. We show that sea surface warming in the Northeast Atlantic is accompanied by increasing phytoplankton abundance in cooler regions and decreasing phytoplankton abundance in warmer regions. This impact propagates up the food web (bottom-up control) through copepod herbivores to zooplankton carnivores because of tight trophic coupling. Future warming is therefore likely to alter the spatial distribution of primary and secondary pelagic production, affecting ecosystem services and placing additional stress on already-depleted fish and mammal populations.     

Lunar receiving laboratory

The Lunar Receiving Laboratory will be the permanent depository of a portion of the collection of lunar samples; it will safeguard the collection, providing continuing security and ensuring scientific integrity. In carrying out the time-dependent experiments and continuing functions of the laboratory, NASA will rely on visiting expert scientists supplementing a relatively small resident staff; outside scientists will be relied upon for most investigations and detailed analyses of samples. It is believed that the designed procedures and facilities provided will ensure the maximum scientific return from the Apollo Program in the way of information from lunar samples.     

Experimental petrology of lunar material: the nature of mascons, seas, and the lunar interior

One-atmosphere melting data show that Apollo 11 samples are near cotectic. Melting relations at pressures up to 35 kilobars show that clinopyroxenite or amphibole peridotite are possible lunar interiors. Mascons cannot be eclogite; they may be ilmenite accumulate. Hot lunar surface material will boil off alkalis.     

Impact-induced seismic activity on asteroid 433 Eros: a surface modification process

High-resolution images of the surface of asteroid 433 Eros revealed evidence of downslope movement of a loose regolith layer, as well as the degradation and erasure of small impact craters (less than approximately 100 meters in diameter). One hypothesis to explain these observations is seismic reverberation after impact events. We used a combination of seismic and geomorphic modeling to analyze the response of regolith-covered topography, particularly craters, to impact-induced seismic shaking. Applying these results to a stochastic cratering model for the surface of Eros produced good agreement with the observed size-frequency distribution of craters, including the paucity of small craters.